David thomas



mill-l7 4 Patented Apr. 14, 1896.

METALLIC PACKING.

D. THOMASQJ. E. BAKER 8v F. TUNES.

punumm (No Model.) 7

NITED STATES DAVID THOMAS, OF DINAS, JOHN ERNEST BAKER, OF CARDIFF,-AND FRANK JONES, OFBASSALEG, ENGLAND.

METALLIC PACKING.

srEoIEIcATIoN forming part of Letters Patent No. 558,236, dated. April 14, 1896.

Application filed December 26, 1895. Serial No. 573,336. (No model.) Patented in England December 20,1894, No. 24,754,

and November 13,1895, No. 21,584.

To all whom it may concern:

Be it known that we, DAVID THOMAS, of

The Cottage, Din-as, near Pontypridd, J oHN' ERNEST BAKER, of No. 209 Newport Road, Cardiff, in the county of Glamorgan, and FRANK J ONES, of The Vicarage, 13assaleg, near Newport, in the county of Monmouth,

England, have invented certain new and use declare that the following is a full, clear, andexact description of the invention, reference being made to the accompanying drawings, which are to be taken as part of this specification and read therewith, and one which will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved metallic packing applicable to piston rods" or plungers and to the pistons of steam or other engines or pumps, so as to render the same steam or water tight against the resilience of any elastic fiuid under pressure.

The invention consists of the features which will now be described, and particularly pointed out in the claims.

In the accompanying sheet of drawings, Figure 1 represents a vertical section, partly in elevation, of astuffing-box fitted with our improved metallic packing. Fig. 2 represents a piston, half in section and half in elevation, fitted with our improved'packing; and Fig. 3 is a similar View of a modified construction of piston and packing with the piston-rod omitted.

In Fig. 1, A is the stuffing-box, 13 its gland, O O the bushes, and D the piston rod or plunger to be packed, all these parts 'bein g of similar construction as heretofore.

E is the spiral spring-coil, which is of larger diameter in the middle than at any other point, decreasing in diameter toward each end gradually and equally, thus taking the shape of two equal cones placed base to base.

F F are the two cups embracing each half of the coil. They are both of the same size, and the bottom or outer end of each is bored to fit the periphery of the rod D and their peripheries turnedto fit truly in the stuffingbox. Their insides are turned to the same taper as the respective half spring or coil. The length of each cup is less than half the depth of the stuffingbox, so as to provide a clear space G for permitting a certain amount of play between the inner ends of the cups. A space H is also provided between the bot tom or outer end of each cup and the respective end of the spring-coil for receiving the said end of the latter as it is forced away from the center upon the cups being forced toward one another.

I Iare packings of loose material interposed between the outer ends or bottoms of the cups and the respective bushes O, and J is a packing of loose material between the turns of the spiral coil E.

The action is as follows: As the gland B is screwed up the cup F is forced toward the cup F, thus tightening up or forcing the spring-coil E against the periphery of the rod D. Pressure from the cylinder or other source of power between the inner bush 0 and said rod D bears against the outer end of the inner cup F and forces it over the respective end or half of the spring-coil, thus pressing the latter into closer contact with the periphery of the rod D.

Figs. 2 and 3 show the application of our invention to the pistons of engines or pumps, half being in section and half in elevation, the said pistons being shown of small diameter applicable to pumps.

In Fig. 2, K represents the body of the piston, and L L are the walls of the cylinder. E is the spiral spring-coil, as before described, and R R are conical rings embracing the two halves of the double-coned spiral spring in a similar but reverse manner to that already described with reference to the cups F F- that is to say, the said rings bear on their inner flat surfaces against the body of the piston, while their outer coned surfaces bear against the spiral coil E. These rings are forced toward each other by the steam or other pressure passing through openings or passages IVI M, formed in the piston,thus causing the spiral coil to be forced outwardly against the inner surface of the cylinder. N N is the annular surface which gives the requisite area for the steam acting upon the flat face of the conical rings R R. This area is varied to suit the pressure employed, it being greater for low pressures and less for high pressures. J is the packing of loose material placed between the turns or coils of the spiral spring. S is the piston-rod, and S the nut for securing the piston thereon.

In Fig. 3 the piston is represented as split into two parts at the center A, K being the body thereof and O the junk-ring, the pistonrod being omitted. In this arrangement we provide a cup-leather packing P, inserted in a groove turned in the junk-ring on body of the piston, the internal pressure within the said cup-leather keeping the joints of the conical rings R R tight, while at the same time permitting the said rings to advance toward each other and force out the spiral coil E, as before described.

Q, Q are setscrews screwed into tapped holes in the conical rings. These screws are for the purpose of tightening up the rings, a collar Q being formed on each screw, fitting into a recess in the junk-ring and body or end flange of the piston, the screws having square heads or ends for the application of a boxspanner for this purpose.

\Ve claim- 1. A packing for glands, pistons or the like comprising the spring of conical form, the packing material between the spirals of the spring and the adjustable section conforming to the spring to exert pressure thereon, substantially as described.

2. A packing for glands, pistons or the like, comprising spring of conical form, the packing material between the coils and bearing together with the edges of said coils upon the surface to be packed and the adjustable section to press upon the spring, substantially as described.

3. In combination, in a packing, the spring of conical form, the adjustable section to press on the spring, a support for the spring and section, and a steam-port M to supply steam-pressure to the parts, substantially as described. 4. In combination, in a packing, the spring of conical form, the adjustable section, the support, for the section and spring, said support having a steam-channel and the cupleather P, substantially as described.

In Witness whereof we have hereunto af fixed our signatures, in presence of two witne'sses, this 12th day of December, 1805.

DAVID THOMAS, JOHN ERNEST BAKER. FRANK JONES. \Vitnesses:

SAMUEL WESL Y ALLEN, FRANK. IIowELLs. 

